I dont know what is wrong with my maxima, sometimes it doesnt wanna start right away so i have to turn the key twice for it to start and press the gas because without the gas it will die, so i press the gas a bit so it doesn't die, it only happens ocasionally, when the car is cold.
This isnt the biggie. I have been getting about 260-280 miles on my full tank of premium gas. I dont know what is wrong please help, any suggestions will be much appreciated

 

260-280 on the highway or main road?

 

25% highway then 75% city streets

 

There are many ways to address your issue, do you have a check engine light on? Have you done a tune-up? Is your air filter dirty? Are your tire pressures correct? etc...

 

I didnt tune up the car yet, it has about 74,000 miles, my check engine is not on, it was on a while back so i changed the o2 sensors, and canceled it so it never came back on. my air filter is K&N n i bought it 6 months ago, my tire pressures are correct.

 

^why would you cancel your check engine light? Theres nothing wrong with knowing your car needs to be modified to work better.

 

I mean i cleared it, when i changed the o2 sensors.

 

It appears that you have never replaced your spark plugs. Replace them with NGK coppers, or laser platinums. For my money, I would go the NGK laser platinum route.

 

I agree with Bobo about changing the spark plugs, I would also see if there are any "ghost codes" left in the system. Call me crazy but I first changed my plugs @ 100k miles, and I have never replaced my knock sensor, but I have replaced all O2 sensors, left bank twice. Car has 136k on it and starts without touching the gas.

 

...definitely check for remaining codes in the system. it sounds crazy but i used to think that tire pressure wouldn't affect your mileage, i have found now that it certainly benifits you to maintain the proper pressure.

 

thanks a lot guys!

 

Test your knock sensor with a multimeter, harness has two wires black and clear right near the right corner of the front valve cover. I would also change the plugs with NGK type R platinum plugs from the dealership, I wouldn't use bosch plugs I have heard they suck in Nissans. Once I changed my plugs my mileage and performance was restored, the old ones had a thick layer of carbon all over the tip.

 

I'm currently using the BOSCH Quad-Fire plugs and they're running pretty decently, haven't had any issues with those. Has anyone has issues using BOSCH plugs?

 

I get about 18mpg average, 50% highway/city, ~250miles/tank. I haven't replaced anything engine-wise in the past 15k miles (dunno what the owner did before that) and it has 163k on it. I've sort of accepted this as normal though.

 

It's not that normal I get over 100 more than you in all city driving.

 

Well my right foot isn't exactly light if you know what I mean.

 

lol same here. i get like 20 around town, 24-28 highway

there are soooooooooooooooooo fcukin many of these gas milage threads

 

I agree. And we can help all we can, but it doesn't matter since there are tons of reasons why someone's gas mileage could be bad. Basically every engine control feature could be a reason. Filters, and physical aspects too.

 

check spark plugs, fuel injectors, fuel filter. i used to have to press the gas at first to keep my car from dying out. i ran some fuel injector cleaner through the tank and haven't had the problem since.

 

I am confused on the gas mileage you guys are getting. I am running 89 octane, and get about 380-410 per tank. When i seen people getting 260, im like, damn, something is got to be wrong with that

 

Yeah same here.